Answer:
See explanation section
Step-by-step explanation:
Requirement A)
According to the graph, whenever Sarah purchased one comic book, she lost $5 from her allowance. Now the allowance remain after purchasing one comic book = ($100 - 5) = $95
Whenever she purchased three comic books, she lost $5 × 3 = $15 from her allowance. Now the allowance remain after purchasing three comic books = ($100 - 15) = $85. In that way, she lost her $50 after purchasing 10 comic books from her allowance. Therefore, the rate of change is $5.
Requirement B)
It represents that she spent $5 on her each comic book. It also represents that her each book decreases her allowance by $5.